結果
| 問題 |
No.1424 Ultrapalindrome
|
| コンテスト | |
| ユーザー |
 LayCurse
|
| 提出日時 | 2021-03-12 22:48:31 |
| 言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 5,482 bytes |
| コンパイル時間 | 2,571 ms |
| コンパイル使用メモリ | 213,820 KB |
| 最終ジャッジ日時 | 2025-01-19 15:26:46 |
|
ジャッジサーバーID （参考情報） |
judge5 / judge2 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 25 WA * 4 |
コンパイルメッセージ
In member function ‘void graph::getDist(int, int*, void*)’,
inlined from ‘int graph::TreeDiameter(int&, int&, void*)’ at main.cpp:202:12,
inlined from ‘int main()’ at main.cpp:247:21:
main.cpp:135:9: warning: ‘x’ may be used uninitialized [-Wmaybe-uninitialized]
135 | res[root]=0;
| ^~~~
main.cpp: In function ‘int main()’:
main.cpp:229:7: note: ‘x’ was declared here
229 | int x;
| ^
main.cpp:249:12: warning: ‘y’ may be used uninitialized [-Wmaybe-uninitialized]
249 | g.getDist(y, d2);
| ~~~~~~~~~^~~~~~~
main.cpp:230:7: note: ‘y’ was declared here
230 | int y;
| ^
ソースコード
#pragma GCC optimize ("Ofast")
#include<bits/stdc++.h>
using namespace std;
void*wmem;
char memarr[96000000];
template<class T> inline void walloc1d(T **arr, int x, void **mem = &wmem){
static int skip[16] = {0, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1};
(*mem) = (void*)( ((char*)(*mem)) + skip[((unsigned long long)(*mem)) & 15] );
(*arr)=(T*)(*mem);
(*mem)=((*arr)+x);
}
template<class T> inline void walloc1d(T **arr, int x1, int x2, void **mem = &wmem){
walloc1d(arr, x2-x1, mem);
(*arr) -= x1;
}
inline int my_getchar_unlocked(){
static char buf[1048576];
static int s = 1048576;
static int e = 1048576;
if(s == e && e == 1048576){
e = fread_unlocked(buf, 1, 1048576, stdin);
s = 0;
}
if(s == e){
return EOF;
}
return buf[s++];
}
inline void rd(int &x){
int k;
int m=0;
x=0;
for(;;){
k = my_getchar_unlocked();
if(k=='-'){
m=1;
break;
}
if('0'<=k&&k<='9'){
x=k-'0';
break;
}
}
for(;;){
k = my_getchar_unlocked();
if(k<'0'||k>'9'){
break;
}
x=x*10+k-'0';
}
if(m){
x=-x;
}
}
struct MY_WRITER{
char buf[1048576];
int s;
int e;
MY_WRITER(){
s = 0;
e = 1048576;
}
~MY_WRITER(){
if(s){
fwrite_unlocked(buf, 1, s, stdout);
}
}
}
;
MY_WRITER MY_WRITER_VAR;
void my_putchar_unlocked(int a){
if(MY_WRITER_VAR.s == MY_WRITER_VAR.e){
fwrite_unlocked(MY_WRITER_VAR.buf, 1, MY_WRITER_VAR.s, stdout);
MY_WRITER_VAR.s = 0;
}
MY_WRITER_VAR.buf[MY_WRITER_VAR.s++] = a;
}
inline void wt_L(char a){
my_putchar_unlocked(a);
}
inline void wt_L(const char c[]){
int i=0;
for(i=0;c[i]!='\0';i++){
my_putchar_unlocked(c[i]);
}
}
template<class T, class S> int arrCountVal(int N, T A[], S val){
int i;
int res = 0;
for(i=(0);i<(N);i++){
if(A[i]==val){
res++;
}
}
return res;
}
struct graph{
int N;
int*es;
int**edge;
void setEdge(int N__, int M, int A[], int B[], void **mem = &wmem){
int i;
N = N__;
walloc1d(&es, N, mem);
walloc1d(&edge, N, mem);
for(i=(0);i<(N);i++){
es[i] = 0;
}
for(i=(0);i<(M);i++){
es[A[i]]++;
es[B[i]]++;
}
for(i=(0);i<(N);i++){
walloc1d(&edge[i], es[i], mem);
}
for(i=(0);i<(N);i++){
es[i] = 0;
}
for(i=(0);i<(M);i++){
edge[A[i]][es[A[i]]++] = B[i];
edge[B[i]][es[B[i]]++] = A[i];
}
}
void getDist(int root, int res[], void *mem = wmem){
int i;
int j;
int k;
int*q;
int s;
int z;
walloc1d(&q, N, &mem);
for(i=(0);i<(N);i++){
res[i]=-1;
}
res[root]=0;
s=0;
z=1;
q[0]=root;
while(z){
i=q[s++];
z--;
for(j=(0);j<(es[i]);j++){
k=edge[i][j];
if(res[k]>=0){
continue;
}
res[k]=res[i]+1;
q[s+z++]=k;
}
}
}
int getDist(int a, int b, void *mem = wmem){
int i;
int j;
int k;
int*q;
int s;
int z;
int*d;
if(a==b){
return 0;
}
walloc1d(&d, N, &mem);
walloc1d(&q, N, &mem);
for(i=(0);i<(N);i++){
d[i] = -1;
}
d[a] = 0;
s = 0;
z = 1;
q[0] = a;
while(z){
i = q[s++];
z--;
for(j=(0);j<(es[i]);j++){
k = edge[i][j];
if(d[k] >= 0){
continue;
}
d[k] = d[i] + 1;
if(k==b){
return d[k];
}
q[s+z++] = k;
}
}
return -1;
}
int TreeDiameter(int &a, int &b, void *mem = wmem){
int i;
int mx;
int*d;
walloc1d(&d, N, &mem);
getDist(0, d, mem);
mx = -1;
for(i=(0);i<(N);i++){
if(mx < d[i]){
mx = d[i];
a = i;
}
}
getDist(a, d, mem);
mx = -1;
for(i=(0);i<(N);i++){
if(mx < d[i]){
mx = d[i];
b = i;
}
}
return mx;
}
int TreeDiameter(void *mem = wmem){
int a;
int b;
return TreeDiameter(a, b, mem);
}
}
;
int N;
int A[100000];
int B[100000];
graph g;
int d1[100000];
int d2[100000];
int d[100000];
int main(){
int i;
wmem = memarr;
int x;
int y;
int m;
int mx = -1;
rd(N);
{
int Lj4PdHRW;
for(Lj4PdHRW=(0);Lj4PdHRW<(N-1);Lj4PdHRW++){
rd(A[Lj4PdHRW]);A[Lj4PdHRW] += (-1);
rd(B[Lj4PdHRW]);B[Lj4PdHRW] += (-1);
}
}
g.setEdge(N,N-1,A,B);
if(arrCountVal(N,g.es,1) == 2){
wt_L("Yes");
wt_L('\n');
return 0;
}
m = g.TreeDiameter(x, y);
g.getDist(x, d1);
g.getDist(y, d2);
for(i=(0);i<(N);i++){
if(d1[i]==d2[i] && mx < d1[i]+d2[i]){
mx = d1[i]+d2[i];
m = i;
}
}
g.getDist(m, d);
mx = -1;
for(i=(0);i<(N);i++){
if(g.es[i]==1 && i!=m){
if(mx == -1){
mx = d[i];
}
if(mx != d[i]){
wt_L("No");
wt_L('\n');
return 0;
}
}
}
wt_L("Yes");
wt_L('\n');
return 0;
}
// cLay version 20210227-1
// --- original code ---
// int N, A[1d5], B[1d5];
// graph g;
// int d1[1d5], d2[1d5], d[1d5];
// {
// int x, y, m, mx = -1;
// rd(N,(A--,B--)(N-1));
// g.setEdge(N,N-1,A,B);
// if(arrCountVal(N,g.es,1) == 2) wt("Yes"), return 0;
// m = g.TreeDiameter(x, y);
// g.getDist(x, d1);
// g.getDist(y, d2);
// rep(i,N) if(d1[i]==d2[i] && mx < d1[i]+d2[i]) mx = d1[i]+d2[i], m = i;
// g.getDist(m, d);
// mx = -1;
// rep(i,N) if(g.es[i]==1 && i!=m){
// if(mx == -1) mx = d[i];
// if(mx != d[i]) wt("No"), return 0;
// }
// wt("Yes");
// }